android AutoCompleteTextView+ SQLite

android AutoCompleteTextView+ SQLite 数据库保存搜索记录

搜索中需要记录用户的搜索历史，以方便用户在下次搜索时快捷搜索。

思路：

使用SQLite作为用户输入的记录，当用户查询时从数据库中取出数据作为AutoCompleteTextView的数据源。

具体代码：

1.在main.xml 或者 自己定义的xml文件中 增加 AutoCompleteTextView

<AutoCompleteTextView android:id="@+id/search_text" android:layout_width="0dip"
   android:layout_height="wrap_content" android:layout_weight="1.0"
   android:layout_marginTop="6dip" android:layout_marginBottom="6dip"
   android:clickable="true" android:inputType="none"
   android:textSize="18sp" android:textStyle="normal"
   android:textColor="@android:color/primary_text_light"
   android:textColorHint="@color/search_hint" />

2.数据库操作，这里可以写你自己具体的数据库操作，下面是我的代码

public class Complete_Db {

 public static SQLiteDatabase db;
 public static String filepath;
 public static void CreateDB(String dbName,Context context){
  filepath = context.getFilesDir().toString()+"/"+dbName;
  db = SQLiteDatabase.openOrCreateDatabase(filepath, null);
 }
 public static boolean Insert(String name){
  boolean result = false;
  try{
  System.out.println("db state:"+db.isOpen());
  if(!db.isOpen())
   db.openOrCreateDatabase(filepath, null);
  ContentValues value = new ContentValues();
  value.put("name", name);
  db.insertOrThrow("input", null, value);
//  db.execSQL("insert into input values(null,?)",new String[]{name});
  }catch(SQLException e){
   e.printStackTrace();
   db.execSQL("create table input(id integer primary key autoincrement,name varchar(100))");
   ContentValues value = new ContentValues();
   value.put("name", name);
   db.insertOrThrow("input", null, value);
//   db.execSQL("insert into input values(null,?)",new String[]{name});
  }
  finally{
   Log.i("insert into db",name);
  }
  return result;
 }
 public static Cursor Query(String query){
  
  if(query != null){
   try{
    if(!db.isOpen())
     db.openOrCreateDatabase(filepath, null);
    String selection = "name like \'" + query +"%\'";
             return db.query("input",new String[]{"name"}, selection, null, null, null, null);
   }
   catch(SQLException e)
   {
    db.execSQL("create table input(id integer primary key autoincrement,name varchar(100))");
    String selection = "name like \'" + query +"%\'";
             return db.query("input",new String[]{"name"}, selection, null, null, null, null);
   }
   
  }
  else
   return null;
 }
 public static void Close(){
  if(db!=null && db.isOpen())
   db.close();
 }
 public static void Clear(){
  //清空搜索数据库
  
  try{
  if(!db.isOpen())
   db.openOrCreateDatabase(filepath, null);
  db.execSQL("delete * from input");
  }catch(SQLException e){
   e.printStackTrace();
  }
 }
}

3.在Activity 中调用

AutoCompleteTextView  searchText = (AutoCompleteTextView)findViewById(R.id.search_text);

Complete_Db.CreateDB("search.db", SearchActivity.this);
     List<String> search_hint = new ArrayList<String>();
  System.out.println("query string :"+searchText.getText().toString().trim());
   Cursor cursor = Complete_Db.Query(searchText.getText().toString().trim());
    cursor.moveToFirst();
  while(cursor.isAfterLast() == false){
   Log.i("query result",cursor.getString(0));
   search_hint.add(cursor.getString(0));
   cursor.moveToNext();
  }
      
    search_hint.add("清除历史");//用于清除历史记录
    String hints[] = new String[search_hint.size()];
    search_hint.toArray(hints);
    ArrayAdapter<String> adapter= new ArrayAdapter<String>(
            SogouSearchActivity.this, R.layout.auto_complete_list,hints);
        for(int i=0;i<hints.length;i++){
         System.out.println("db string:"+hints[i]);
        }

          searchText.setAdapter(adapter);
          cursor.close();
          searchText.setThreshold(1);
          searchText.setOnItemClickListener(new OnItemClickListener() {

     public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
       long arg3) {
      // TODO Auto-generated method stub
      if(searchText.getText().toString().equals("清除历史")){
       Log.i("touch clear","history");
       Complete_Db.Clear();
       searchText.setText(null);
      }
     }
   });

   另外需要增加一个事件，用于监听当输入改变时从数据库中取数据：

 searchText.addTextChangedListener(new TextWatcher() {

            public void afterTextChanged(Editable s) {
                // TODO Auto-generated method stub
                List<String> search_hint = new ArrayList<String>();   
          System.out.println("query string :"+searchText.getText().toString().trim());
          Cursor cursor = Complete_Db.Query(searchText.getText().toString().trim());
          cursor.moveToFirst();
          while(cursor.isAfterLast() == false){
           Log.i("query result",cursor.getString(0));
           search_hint.add(cursor.getString(0));
           cursor.moveToNext();
          }
                 search_hint.add("清除历史");
            String hints[] = new String[search_hint.size()];
            search_hint.toArray(hints);
            ArrayAdapter<String> adapter= new ArrayAdapter<String>(
                    SogouSearchActivity.this, R.layout.auto_complete_list,hints);
                for(int i=0;i<hints.length;i++){
                 System.out.println("db string:"+hints[i]);
                }
                  searchText.setAdapter(adapter);
            }

            public void beforeTextChanged(CharSequence s, int start, int count,
                    int after) {
                // TODO Auto-generated method stub
            }
 
            public void onTextChanged(CharSequence s, int start, int before,
                    int count) {
                    Log.i("text",s.toString());
                // TODO Auto-generated method stub
            }
          });

 

 @Override
    public void onDestroy(){
     super.onDestroy();
     Complete_Db.Close();
    }